Positioning information for drones, machines, or other equipment has always been valuable. With fifth generation (5G) and long-term evolution (LTE) there are new possibilities to provide positioning information using the cellular network. When positioning information is available through the cellular network, having a standardized way of exposing positioning information would benefit a various number of applications. Thus, determining what requirements such an application programming interface (API) should have is important for future work. This thesis investigates and analyzes requirements that every API for exposing positioning information must have. It provides a theoretical reference API, the positioning exposure protocol (PEP), that fulfill all requirements. Additionally, the thesis analyzes available APIs on the market, and compares each and every one of them against the PEP, constructing a list of changes and extensions to make them compliant. The most compliant and suitable API is the gateway mobile location center (GMLC) API, which only requires a few changes and extensions to be functionally equivalent and fulfill allrequirements.